Field of the Invention
The present invention relates to a motor driving apparatus for driving a motor.
Related Art
A conventional motor driving apparatus controls a motor by receiving the signal output by a detector (encoder) attached to the motor, and calculating the position, the speed and the like of the motor. In the case where the signal output by the detector is a so-called A/B phase signal which is an analog sine/cosine wave pair, in general, the motor driving apparatus performs processing of: cutting high frequency noise with a low-pass filter; appropriately amplifying the amplitude thereof; performing A/D conversion to obtain a digital value; and converting the digital value into an angle of the motor to calculate the position, the speed and the like (refer to Patent Document 1, as an example).
Patent Document 1: Japanese Unexamined Patent Application, Publication No. 2002-199768